944 EXPERIMENT STATION RECORD. 



smallest percentage was found in the stems and hulls. The dry matter of the plants 

 contained an average of 0.206 per cent, 0.115 per cent being found in the stems and 

 leaves and 0.091 per cent in the grains. The stems contained two-thirds the quan- 

 tity of magnesia found in the leaves. The grains of the pot and field-grown samples 

 contained the same amount of magnesia, but the stems and leaves of the pot-grown 

 samples contained a higher percentage than the stems and leaves of the field samples. 



The highest absolute quantity of sulphur was found in the grains. The sulphur 

 content was found to increase and decrease simultaneously in all parts of the plant. 

 The stems and leaves showed the greatest variations. The average sulphur content 

 in the dry matter of the plant was 0.15 per cent, of which C.068 per cent was con- 

 tained in the kernels. 



The content of salicylic acid was highest in the leaves and much lower in the stems 

 and grains. In general the distribution of salicylic acid in the plant was the same as 

 the distribution of lime, but in most parts of the plant the salicylic acid content was 

 about 7 times the lime content, and in the grain it was even 12 times as great. 

 Plants grown on moor, sandy, and sandy loam soils were lowest in salicylic acid, while 

 the plants from clay and chalky loam soils gave the highest figures. The content of 

 salicylic acid in the stems and leaves of the plant seemed to be governed by the quan- 

 tity of readily soluble salicylic acid combinations in the soil. 



In studying the effect of different plant food solutions plants were grown in pots 

 filled with sand according to the sand-culture method of Hellriegel, but in several 

 instances different agricultural soils were used in place of sand. Each series of pots 

 contained one element of plant food in different quantities, while the other elements 

 remained constant. The plants from each pot were dried at 100° C, then'weighed 

 and analyzed. The roots were not taken into consideration, the analysis being 

 limited to the grains and the portion of the plant above ground without the grains. 

 These experiments were conducted for a series of years. 



Four of the nitrogen series showed an increase in the nitrogen content of the 

 plants as the quantity of nitrogen furnished in the plant food increased. In 2 series 

 the nitrogen figures for the grains and for plants not fully rii:)e were about constant. 

 According to the author, a definite factor which would indicate the nitrogen content 

 associated with a maximum yield is not to be deduced from the results. In one 

 series the best yields showed 1.81 to 1.94 per cent of nitrogen in the grains; in 

 another series, 1.44 jjer cent; in a third, 1 per cent. In one instance of plants 

 analyzed before fully ripe the maximum yield was associated with a nitrogen content 

 of 2.03 per cent. 



In studying the effects of phosphoric acid it was found that in 8 different series the 

 increase in phosphoric acid in the plant food increased the content of that element 

 in the grains, while in 3 series it remained constant at 0.85 per cent. The striking 

 difference between the results of these 3 series and the others is not explained. 



In all the potash series the increase of potash in the plant food increased the potash 

 content in the stems and leaves of ripe and not fully ripe plants. Three series con- 

 tinued for 3 successive years with only an initial application of potash showed a 

 decreasing potash content in the plants from year to year. The potash content was 

 never constant in the stems and leaves when the quantity of potash in the fertilizer 

 varied, but in the grain it remained constant or varied very slightly. 



The results of 3 tests with different quantities of lime showed that a decrease in 

 the quantity of lime furnished the plant caused a decrease of that constituent in the 

 stems and leaves of ripe as well as unripe plants. The lime content of the plants 

 in these series varied from 0.10 to 0.18 per cent, which proved too low a figure for 

 their healthy development. 



The magnesia content of the stems and leaves increased in these tests with the 

 quantity of magnesia furnished the plant as food. With an ^isufficient supply the 

 content in the unripe plants and in the mature haufms and grains sank to below 0.15 



